Question 1

What is the hybridization of the S atom in SF4?

Accepted Answer

A)  sp3d 
B)  sp3 
C)  sp3d2 
D)  sp4 
A)  sp3d 
B)  sp3 
C)  sp3d2 
D)  sp4

Question 2

Unhybridized p orbitals must be present for electron delocalization to occur.

Accepted Answer

A) True 
 B)False

Question 3

Choose the INCORRECT statement about SnCl2.

Accepted Answer

A)  The hybridization of Sn is sp2. 
B)  The molecule is linear. 
C)  There is one lone pair of electrons on Sn. 
D)  There are no π bonds. 
E)  There are two σ bonds. 
A)  The hybridization of Sn is sp2. 
B)  The molecule is linear. 
C)  There is one lone pair of electrons on Sn. 
D)  There are no π bonds. 
E)  There are two σ bonds.

Question 4

Choose the INCORRECT statement about PCl5.

Accepted Answer

A)  There are no π bonds. 
B)  P has one lone pair. 
C)  P has sp3d hybridization. 
D)  Each Cl has 3 lone pairs. 
E)  There are 5 σ bonds. 
A)  There are no π bonds. 
B)  P has one lone pair. 
C)  P has sp3d hybridization. 
D)  Each Cl has 3 lone pairs. 
E)  There are 5 σ bonds.

Question 5

According to M.O. theory, which is an INCORRECT statement for H2-?

Accepted Answer

A)  The B.O. is 1/2. 
B)  There are no unpaired electrons. 
C)  The σ1s* orbital has one electron. 
D)  The molecule is paramagnetic. 
E)  There are 3 electrons in the molecular orbitals. 
A)  The B.O. is 1/2. 
B)  There are no unpaired electrons. 
C)  The σ1s* orbital has one electron. 
D)  The molecule is paramagnetic. 
E)  There are 3 electrons in the molecular orbitals.

Question 6

Which statement is INCORRECT about molecular orbital theory?

Accepted Answer

A)  The number of molecular orbitals produced is equal to the number of atomic orbitals combined. 
B)  Each pair of sigma molecular orbitals is a bonding orbital and an antibonding orbital. 
C)  The antibonding orbital is at a lower energy than the bonding orbital. 
D)  The bond order (BO) is   . 
E)  Hund's rule says that each orbital of identical energy has one electron before pairs are formed. 
A)  The number of molecular orbitals produced is equal to the number of atomic orbitals combined. 
B)  Each pair of sigma molecular orbitals is a bonding orbital and an antibonding orbital. 
C)  The antibonding orbital is at a lower energy than the bonding orbital. 
D)  The bond order (BO) is   . 
E)  Hund's rule says that each orbital of identical energy has one electron before pairs are formed.

Question 7

According to MO theory, assuming that the molecular orbits are the same as a diatomic molecule, which is an INCORRECT statement for CN-?

Accepted Answer

A)  The BO is 2. 
B)  There are no unpaired electrons. 
C)  The σ2p is the highest filled level. 
D)  The molecule is diamagnetic. 
E)  There are 10 electrons in the n=2 level orbitals. 
A)  The BO is 2. 
B)  There are no unpaired electrons. 
C)  The σ2p is the highest filled level. 
D)  The molecule is diamagnetic. 
E)  There are 10 electrons in the n=2 level orbitals.

Question 8

Which of the following statements concerning the carbon dioxide molecule is correct?

Accepted Answer

A)  The molecule contains two lone pairs of valence electrons. 
B)  The molecule contains two σ bonds. 
C)  The molecule contains four π bonds. 
D)  The carbon is described by sp2 hybridization. 
E)  Each oxygen is described by sp3 hybridization. 
A)  The molecule contains two lone pairs of valence electrons. 
B)  The molecule contains two σ bonds. 
C)  The molecule contains four π bonds. 
D)  The carbon is described by sp2 hybridization. 
E)  Each oxygen is described by sp3 hybridization.

Question 9

The electrical conductivity of semiconductors increases with increasing temperature.

Accepted Answer

A) True 
 B)False

Question 10

Which of the following statements concerning molecular orbital (MO) theory is FALSE?

Accepted Answer

A)  The number of MOs formed equals the number of atomic orbitals combined. 
B)  Any set of MOs from 2 atomic orbitals involves 1 bonding and 1 antibonding orbital. 
C)  Electrons normally enter the lowest energy MO available to them. 
D)  No more than two electrons can enter a particular MO. 
E)  Electrons enter MOs of identical energies in pairs before any enter singly. 
A)  The number of MOs formed equals the number of atomic orbitals combined. 
B)  Any set of MOs from 2 atomic orbitals involves 1 bonding and 1 antibonding orbital. 
C)  Electrons normally enter the lowest energy MO available to them. 
D)  No more than two electrons can enter a particular MO. 
E)  Electrons enter MOs of identical energies in pairs before any enter singly.

Question 11

According to the band theory, why is a material such as diamond an insulator?

Accepted Answer

A)  All of the electrons are in the conduction band. 
B)  All of the electrons are tied to nuclei. 
C)  Very few electrons can make the transition over the large energy gap between the valence band and the conduction band. 
D)  The bonds in diamond are too strong to allow atoms to move so no current flows. 
E)  There are no electrons in the valence band. 
A)  All of the electrons are in the conduction band. 
B)  All of the electrons are tied to nuclei. 
C)  Very few electrons can make the transition over the large energy gap between the valence band and the conduction band. 
D)  The bonds in diamond are too strong to allow atoms to move so no current flows. 
E)  There are no electrons in the valence band.

Question 12

Choose the INCORRECT statement about NH4+.

Accepted Answer

A)  The hybridization of N is sp3. 
B)  The molecule is tetrahedral. 
C)  There is one lone pair of electrons on N. 
D)  There are no π bonds. 
E)  There are four σ bonds. 
A)  The hybridization of N is sp3. 
B)  The molecule is tetrahedral. 
C)  There is one lone pair of electrons on N. 
D)  There are no π bonds. 
E)  There are four σ bonds.

Question 13

Which of the following statements is INCORRECT?

Accepted Answer

A)  A double bond is stronger than a single bond for the same atoms. 
B)  A double bond is less than twice as strong as a single bond for the same atoms. 
C)  Bonded atoms cannot rotate freely around a double bond. 
D)  Molecular geometry depends on the σ bond framework. 
E)  There are no hybridized orbitals in multiple bonds. 
A)  A double bond is stronger than a single bond for the same atoms. 
B)  A double bond is less than twice as strong as a single bond for the same atoms. 
C)  Bonded atoms cannot rotate freely around a double bond. 
D)  Molecular geometry depends on the σ bond framework. 
E)  There are no hybridized orbitals in multiple bonds.

Question 14

The valence-bond method describes covalent bonding as the overlap of partially filled orbitals.

Accepted Answer

A) True 
 B)False

Question 15

Which of the following species is paramagnetic?

Accepted Answer

A)  B2 
B)  C2 
C)  N2 
D)  CO 
A)  B2 
B)  C2 
C)  N2 
D)  CO

Question 16

In extrinsic semiconductors, the band width is set by the element and cannot be changed.

Accepted Answer

A) True 
 B)False

Question 17

According to VB theory, sigma bonds are:

Accepted Answer

A)  always present in double bonds 
B)  formed only by p orbitals 
C)  formed only by hybrid orbitals 
D)  formed only by s orbitals 
E)  formed only by unhybridized orbitals 
A)  always present in double bonds 
B)  formed only by p orbitals 
C)  formed only by hybrid orbitals 
D)  formed only by s orbitals 
E)  formed only by unhybridized orbitals

Exam 11: Chemical Bonding II: Additional Aspects

What is the hybridization of the S atom in SF4?

Unhybridized p orbitals must be present for electron delocalization to occur.

Choose the INCORRECT statement about SnCl2.

Choose the INCORRECT statement about PCl5.

According to M.O. theory, which is an INCORRECT statement for H2-?

Which statement is INCORRECT about molecular orbital theory?

According to MO theory, assuming that the molecular orbits are the same as a diatomic molecule, which is an INCORRECT statement for CN-?

Which of the following statements concerning the carbon dioxide molecule is correct?

The electrical conductivity of semiconductors increases with increasing temperature.

Which of the following statements concerning molecular orbital (MO) theory is FALSE?

According to the band theory, why is a material such as diamond an insulator?

Choose the INCORRECT statement about NH4+.

Which of the following statements is INCORRECT?

The valence-bond method describes covalent bonding as the overlap of partially filled orbitals.

Which of the following species is paramagnetic?

In extrinsic semiconductors, the band width is set by the element and cannot be changed.

According to VB theory, sigma bonds are:

Matter - Its Properties and Measurement

Atoms and the Atomic Theory

Chemical Compounds

Chemical Reactions

Introduction to Reactions in Aqueous Solutions

Gases

Thermochemistry

Electrons in Atoms

The Periodic Table and Some Atomic Properties

Chemical Bonding I: Basic Concepts

Intermolecular Forces: Liquids and Solids

Solutions and Their Physical Properties

Chemical Kinetics

Principles of Chemical Equilibrium

Acids and Bases

Additional Aspects of Acid-Base Equilibria

Solubility and Complex-Ion Equilibria

Spontaneous Change: Entropy and Free Energy

Electrochemistry

Main Group Elements I: Groups 1, 2, 13, and 14

Main Group Elements II: Groups 18, 17, 16, 15, and Hydrogen

The Transition Elements

Complex Ions and Coordination Compounds

Nuclear Chemistry 1-41

Structures of Organic Compounds

Reactions of Organic Compounds

Chemistry of the Living State

Filters

What is the hybridization of the S atom in SF₄?

Choose the INCORRECT statement about SnCl₂.

According to M.O. theory, which is an INCORRECT statement for H₂^-?

Choose the INCORRECT statement about NH₄⁺.